The present invention relates to structural framework assemblies, and more particularly, to a novel structural connector for interconnecting metal or plastic angles to provide a load-supporting framing structure or rack with the horizontal joining rods being vertically adjustable in any position with respect to the vertical posts and the corner joints being concealed within the angles.
The conventional multipurpose angle irons have been used extensively for their properties of being relatively inexpensive and easily assembled and disassembled. However, these angle irons have sharp edges at both ends, which are likely to cause injury and cut the clothes particularly during assembly of various framing structures or during transport, and are now being less in use. Furthermore, in assembling into various storage racks the angles have to rely upon bolts or screws which pass directly through the holes in the angles and nuts to hold the various longitudinal and transverse angles together in firmness. In such kind of structural constructions having no reinforcing means, not only will the corner joints lack stability but due to the limitations imposed thereupon by the fitting holes and the distance between holes it is not possible to adjust the vertical positions of the various framing structures swiftly and at will when assembled, thus restricting its flexibility in use. Furthermore, such conventional structures lack aesthetic look because of the arrangement of holes in rows and the exposed corner joints and the screw nuts, in addition to the drawbacks that the protruding nuts might easily hook on the clothes. Another conventional display rack assembled with square or rounded metal pipes has no sharp edges, its surfaces being smooth without holes, aesthetically designed and being even more safety in use. Nevertheless, when several transverse pipes are connected to the main framework of the rack to form an assembly rack with multiple shelves, it is necessary to use for the main framework multi-section pipes joined together by means of joints, no single section pipes can be used here. For a type of assembly rack with multiple shelves, the structural strength and stability are not altogether satisfactory, and because of the permanent position in the joints, it is also not possible to adjust the level of the joints thereby restricting its flexibility in use. If the assembly rack is to be disassembled after use, not only has it to use a hammer to knock the joints off, but the openings at the joining ends of the pipes become enlarged once the rack has been dismantled. Under such conditions, unless those enlarged ends are removed the pipes can not be used again and by that it will also result in trouble in the re-use of the pipes.
References to an alternative and more popular assembly procedure in which the frame members or posts are constructed in a way that they can be joined by suitable fasteners, such as screws or bolts may be had from the disclosure in U.S. Pat. Nos. 4,347,015 and 4,545,490 the latter of which is jointly owned by the present inventor.